二氧化硫对大鼠海马神经元电活动和学习记忆能力的影响

目的从神经电生理学的角度揭示SO2对中枢神经系统的毒性作用。方法采用SO2动式吸入染毒技术使雄性SD大鼠染毒7天,每天6h,SO2的染毒剂量为28mg/m3。用电生理学玻璃微电极细胞外记录的方法,在体观察SO2吸入对大鼠海马CAI区神经元自发放电活动的影响,并通过建立被动回避行为条件反射对大鼠的学习和记忆能力进行测试。结果SO2染毒使大鼠海马CAI区神经元自发放电的时程较对照组显著延长(P<0.001);神经元的平均放电频率显著降低,主要表现为中频放电神经元比例明显下降(P<0.05),而低频放电神经元比例升高;SO2染毒大鼠的学习记忆能力显著下降(P<0.05,P<0.01)。结论SO2具有类似神经毒物作用,可显著抑制大鼠海马CAI区神经元的兴奋性,并干扰和影响学习记忆功能。     

低剂量锰对背根节神经元自发放电的兴奋作用

目的探讨低剂量锰对周围神经系统的毒性作用。方法采用离体灌流背根节(DRG)和单纤维记录神经元自发放电的方法,观察不同剂量氯化锰对DRG神经元自发放电的影响。结果不同浓度氯化锰对有自发放电的神经纤维有兴奋作用,随着剂量增加,兴奋作用增强,呈现一定的剂量关系。但氯化锰对静息神经纤维无兴奋作用。不同剂量氯化锰对自发放电频率的兴奋作用呈现不同模式,1μmolLMnCl2作用后,放电频率持续增高。5μmolLMnCl2作用时,放电频率短时间增加后恢复到对照水平,50μmolLMnCl2作用则呈现放电频率先增高后降低的趋势。结论锰对DRG神经元自发放电有兴奋作用,这可能与轻度锰中毒时出现的感觉异常有关。     

基于小波变换和BP神经网络的视觉诱发电位识别

结合小波变换和BP神经网络对视觉诱发脑电信号（VEP）进行分类而产生脑机接口控制信号。利用一维离散小波变换提取强噪声背景下的低频微弱脑电信号，获取特征向量输入BP神经网络进行事件相关电位模式识别。实验表明，小波变换特征向量提取方法能有效地实现信号的去噪、降维和特征提取，BP神经网络能比较准确地从VEP中识别出事件相关电位，进行10次测试的平均识别正确率为99．375％，有利于产生脑机接口控制信号。     

白细胞介素-1β对大鼠离体室旁核脑片神经元放电活动的影响及其机制

目的 研究白细胞介素-β(interleukin-β,IL-1β)对室旁核神经细胞电活动的影响,并对其细胞机制进行初步探讨,为阐明IL-1β在应激情况下对中枢神经系统某些生理和病理状态的作用和指导临床用药提供理论依据.方法 采用神经元细胞外单位放电记录技术,通过灌流给药观察IL-1β对大鼠下丘脑脑片室旁核(parave...     

HHT在生物雷达回波信号噪声抑制中的应用

目的:利用Hilbert-Huang Transform(HHT)的频率区分特性,对生物雷达回波信号进行处理,去除高频噪声成分,提高生物雷达对生命信息的识别能力。方法:首先对经过预处理的雷达回波信号进行经验模态分解获取其固有模态函数,并根据能量分析方法将固有模态函数区分为有用信号占主导模态与噪声占主导模态2个部分,然后用小波软阈值的方法提取噪声占主导模态部分中的有用成分,与有用信号占主导模态部分的固有模态函数叠加,获取雷达回波信号中的生命信息,实现时目标的识别。结果:HHT有效地去除了生物雷达回波信号中的高频噪声成分,提取出了人体呼吸信号。结论:与传统傅里叶去噪方法相比,HHT分辨率更高,能保留信号中的细节特征,为生命体目标的识别提供了更多的信息。     

数字化视频脑电图诊断癫痫更准确

癫痫是患者的脑部细胞不断异常放电的结果,记录和捕捉到这些异常的脑电波,可以帮助医生确诊是否癫痫,癫痫的类型和病灶部位.但脑电波是一种非常微弱的信号,非常容易受到外部的干扰,如病人轻微的动作,外界的语言、动作刺激等,都会影响仪器的接收信号.普通脑电图检查只是记录下患者的脑部电波变化情况,对不太频繁的脑部病灶细胞异常放电有时就难以捕捉到,其诊断的阳性率通常在50%左右.……     

生物雷达检测中呼吸和心跳实时分离技术的研究

目的：从生物雷达检测到的体动信号中分离出心跳信号。方法：采用自适应噪声抵消模型,基于递归最小二乘算法（recursive-leastsquare,RLS）调整模型的输出,并将分离出的心跳信号与心电信号进行比较。结果：该方法可以从体动信号中分离出心跳信号,而且从心跳信号中提取的心率值与从心电信号提取的心率值具有很强的相关性。结论：基于自适应噪声抵消技术,可以实现生物雷达检测中呼吸和心跳的分离。     

基于自适应RLS算法的非接触式生命参数检测中呼吸和心跳信号的分离

目的：从生物雷达非接触式检测所得生命参数信号中提取心跳信号,实现呼吸和心跳信号的有效分离。方法：首先用生物雷达采集系统采集由呼吸引起的携带有心跳等信号的体表微动信号,其次对采集的信号进行预处理．滤除高频噪声,并放大信号,然后运用自适应递归最小二乘（RLS）算法进行处理。结果：自适应RLS算法能够有效地抑制生命参数信号中的呼吸成分,提取出心跳信号。结论：自适应RLS算法可以自动调整自身参数以逐步实现最优处理结果,这对于处理随机性强的生物医学信号十分有效;此外,算法收敛速度快,便于信号实时处理,对临床监护十分有用。     

神经细胞放电的计算机储存和处理系统

1 概述记录和分析神经元的放电活动,是神经电生理研究中最基本的方法。过去主要采用磁带记录和示波器照相法等手段,方法繁琐,费时费力。随着计算机技术的普及,该工作已逐步被各种实时处理系统所代替。但目前大部分单位所采用的实时处理方法都存在一个缺点,即无法保存原始记录,所存入磁盘的结果往往是经处理后的图象数据或某些参数值,不可能对     

雷达式非接触生命参数检测系统中心跳信号提取方法研究

雷达式生命参数检测系统采集的微弱生命参数信号是受到检测对象呼吸及心跳所导致的微动共同作用的复合信号．而且背景噪声随机性较强。为从复合信号中提取出特征明显的心跳信号，采用小波变换的方法，应用Symlets小波将信号各成分分解细化，调节小波分解系数后进行小波重构，从复合信号中提取出规则的心跳信号，为临床监护提供了一种新的非接触检测人体生命参数信号的方法。     

帕金森病患者听觉P300测试及治疗前后的对比研究

目的　探讨帕金森病 (PD)智能障碍及应用左旋多巴等治疗后听觉P3 0 0 (P3 )各项参数的变化。方法　对 3 0例特发性PD患者在治疗前及治疗 6个月后进行常规P3测试 ,并以健康查体者为对照 ,对组间P3各参数进行对比分析。结果　PD患者经过左旋多巴等治疗后 ,除反应时 (RT)有显著 (P <0 0 5 )缩短外 ,其潜伏期 (PL)及波幅 (Amp)均无显著变化 ;PD患者与健康对照组相比 ,无论左旋多巴等治疗前或治疗后 ,其PL及RT均明显延长 (P <0 0 5 ) ,Amp无显著变化。结论　特发性PD患者PL及RT延长 ,提示其存在智能障碍 ,而左旋多巴等治疗后 ,虽然PD患者的运动功能有明显改善 ,但PL及Amp无改善 ,只有RT的改善 ,提示PD患者智能障碍与中枢性多巴胺能神经机制关系不大     

液电膀胱碎石仪的研制

介绍一种体内液电膀胱碎石仪的组成及工作原理，该装置在膀胱镜配合下，经微电极传导，将机内高压放电脉冲引至膀胱，在膀胱内准确跟踪颗粒小，易游走的结石，在距结石5mm处再次放电，产生冲击波，达到击碎结石的目的。     

Microelectrodes and their application in diagnostic medicine

Microelectrodes are in common use in medical detection systems. The binding of two complementary nucleic acid sequences is called hybridization. Today the major obstacle of large-scale hybridization approaches is the large time-dependency of a single reaction, which is up to 16 hours. As the DNA molecules can be electronically charged, the binding could be facilitated and confirmed using an electronic control system. The authors' team aimed to develop a microelectrode system capable for the detection and control of hybridization. A microelectrode head is immersed in small liquid drop. Here, the platinum counterelectrode is surrounded by a non-conducting quartz capillary. The reference electrode is chloridized silver immersed in saturated Ag/Cl dilution. The Ag/AgCl/1 M KCl +AgCl microelectrode in stabilized against the calomel electrode in the first hours, and remains stable between 7th and 30th hours. This can be verified by the minimal drop in the potential difference. Thus the AgCl saturated KCl electrode is usable for several days for actual measurements. The detector is controlled by an attached computer. The system can be used to detect hybridization in a micro-cell located on a gold-plate. The electrode can be dismounted and reused after repeated chloridization of the Ag wire. The microelectrode is simple, cheap; thus is best suited for application in future automated diagnostic detection systems.     

氯化甲基汞对大鼠脑神经细胞c-fos表达的影响

目的通过体内与体外实验相结合的方法研究氯化甲基汞(MMC)对脑神经细胞c-fos表达的影响,探讨甲基汞所致脑发育损伤的机制.方法体外实验中,应用免疫细胞化学方法观察MMC对培养神经元c-fos表达的影响.体内实验中,Wistar妊娠大鼠于妊娠7～10d连续灌胃,每日给予MMC4mg/kg.取出生后第1、3、5、7、10和15d仔鼠大脑组织制备常规组织切片.采用免疫组织化学方法检测c-fos表达.结果体外培养的神经元中加入0.3μmol/LMMC持续作用后,神经元中c-Fos阳性细胞率在0.5h开始增多,并随时间的延长而增加.培养神经元接触MMC10min和2、6h组,细胞阳性率分别为(6.97±2.86)%、(66.86±5.32)%、(64.49±3.09)%.体内实验中,对照组和实验组中仔鼠大脑皮层中c-Fos蛋白阳性细胞率随发育时间延长逐渐减少,但实验组均高于相应对照组,实验组第1、3天组c-Fos阳性率分别为(47.01±3.79)%和(46.71±1.96)%,与对照组的(35.86±3.04)%和(33.35±1.06)%相比,差异有非常显著性.结论MMC可诱导脑神经细胞c-fos的过表达,这可能是MMC所致脑发育损伤的机制之一.     

采用人工流体神经网络实现图象型微粒的检测

在二值微粒图象中，微粒的形态是一封闭的连通区域，微粒检测其实就是连通域的检测。据此，文章提出了采用模拟实际视觉系统扩散行为的人工流体神经网络来实现微粒检测的新方法，并进行了计算机模拟仿真实验，结果证明该方法检测能力强、检测结果准确可靠。     

电磁辐射致小鼠海马神经细胞基因表达谱差异

目的研究电磁辐射后小鼠海马脑区基因表达的变化与神经损伤效应的关系。方法应用cDNA微阵列技术观察电磁辐射后小鼠海马神经细胞基因表达谱的差异，并分析筛选出差异表达基因。结果电磁辐射后即刻小鼠海马神经细胞出现5个上调表达基因。而辐照后24h差异表达基因增加为30个，其中上调表达基因为6个．下调表达基因为24个。差异表达基因主要包括应激蛋白、细胞调亡相关蛋白、信号转导调控因子及效应子、DNA损伤与修复蛋白、转录因子、受体、细胞粘附分子、细胞因子等多种基因。结论电磁辐射可使小鼠海马脑区多个基因出现差异表达，且这种差异表达表现为动态变化。电磁辐射海马神经损伤是一个多基因参与的复杂效应过程，电磁辐射后基因表达的变化规律能够在一定程度上反映出海马神经损伤效应的变化过程。     

Performance management in healthcare: Performance indicator development, task uncertainty, and types of performance indicators

In healthcare, performance indicators are increasingly used to measure and control quality and efficiency of care-providing teams. This article demonstrates that when controllability is emphasized during indicator development, the level of task uncertainty influences the type of resulting performance indicators. We report findings from a field study in a medical rehabilitation centre in The Netherlands, where four low task uncertain teams (‘hand trauma’, ‘heart failure’, ‘amputation’, ‘chronic pain’), and four high task uncertain teams (‘children with developmental coordination disorders (DCD)’, ‘parkinson's disease’, ‘young children (0–4 years) with developmental disorders’, and ‘acquired brain injuries’) participated in the development of performance indicators using the Productivity Measurement and Enhancement System (ProMES) method. Results show that teams higher on task uncertainty developed relatively more process indicators compared to outcome indicators, whereas the reverse was true for teams lower on task uncertainty. Additionally, process indicators developed by high task uncertain teams were more of a problem solving nature than process indicators developed by low task uncertain teams, which had a more procedural character. The study expands existing knowledge by providing a framework which explicates the task processes to be executed under different levels of task uncertainty, and in line with that appropriate performance indicators for healthcare teams.     

Suspected amyotrophic lateral sclerosis? Don't forget diagnostic imaging of the spine

Two patients, men aged 35 and 72 years, had progressive muscle weakness, lower motor neuron signs in all extremities and upper motor neuron signs in the legs. There were no major sensory signs on examination. The clinical picture very much resembled amyotrophic lateral sclerosis (ALS), although there were never brain stem signs. Myelopathy and polyradiculopathies caused by a tandem cervical and lumbar spinal stenosis explained the clinical picture. Cervical MRI and lumbar CT confirmed this diagnosis. Laminectomy was done, after which both patients remained with unchanged symptoms. Tandem spinal stenosis should be part of the differential diagnosis of ALS. Imaging of the spine is necessary to confirm this diagnosis, and in the absence of bulbar signs always necessary prior to the diagnosis of ALS.     

The analysis of neuronal discharge sequences: change-point estimation and comparison of variances

A key problem in neurophysiology is to determine whether, after presentation of a stimulus, there has been a modification in the discharge of a recorded neuron and if so, an attempt is made to estimate the latency of the response. The estimation problem can be considered as that of the estimation of a change-point in a sequence of random variables. The gamma distribution is adequate to model the distribution of intervals between action potentials for different types of neurons. Simulations show that the maximum likelihood estimator based on this model is efficient and robust. An additional problem, in the case of experiments in which a movement follows the stimulus, is to determine whether a response is related to the stimulus or to the movement. A test based on the comparison of marginal scales of a bivariate distribution is proposed. The whole procedure has been tested in simulation and with real examples.     

多间距视网膜表面微电极阵列设计与特性测试

目的：为优化视网膜微电极阵列的设计而设计多间距电极阵列,并对其进行性能测试。方法：采用聚氯代二甲苯（parylene）柔性材料作为柔性衬底,以惰性金属Au作为电极材料,设计不同间距的单排电极阵列,并对微电极阵列的外观、机械性能和柔韧性进行测试。结果：经测试,微电极表面及边缘清晰,导线与电极之间连接完好,连线间无短路。柔韧性检测显示,微电极阵列的柔韧性满足下一步动物实验的要求。结论：设计完成的微电极阵列可为进一步的动物在体视网膜微电极实验提供可靠的条件。